Scientific Name: family Ephemeroptera
Mayflies live underwater as nymphs until they reach maturity, then they hatch into winged adults called duns. The duns molt once more into a spinner that mates, then dies. Before dying, the females lay eggs in the river. A mayfly's adult life is brief, usually only a day or two.
Mayflies are sometimes divided into four major groups based on the behavior of the nymphs:
- Crawlers, who spend their underwater life crawling between rocks and pebbles.
- Clingers, who are flat little things that live in fast water and rarely lose their grip on the bottom.
- Swimmers, who flip their tails and swim.
- Burrowers, who dwell in sediment.
For details on individual species and hatches, use the pull-down menus below. You can look up a species by either its common names (each species may have more than one common name) or scientific name.
ADULT CHARACTERISTICS: Two or three tails; most have two pairs of wings, with the hind set much smaller; wings upright when at rest, except spinners' wings may be splayed to side when dying.